Why does a control have to be on a screen to support voice commands? Most buttons and knobs are just digital inputs into the same infotainment system in current

Why does a control have to be on a screen to support voice commands? Most buttons and knobs are just digital inputs into the same infotainment system in current cars. If the knob or slider is stateful, there are still mechanized versions that can be controlled by software. I had a Kenwood receiver in the 90s that would mechanically turn the knob when I adjusted the volume from the remote and I know Yamaha had a similar feature around the same time. Studio mixing boards (for sound and light) have had software controlled sliders for decades as well. If a $200 stereo can include a servo coupled volume knob, a $30k+ car should have no issue. My Kia has awful rear control where you push a physical button to bring up an ok screen interface that doesn’t react to any physical buttons. Other models have the same physical interface (same buttons, same screen), but allow adjusting the on screen settings with physical buttons. I usually have a lot of kids in the back, and find having to muck with an awful on screen interface (not because it’s on screen, but because they require multiple steps to do things I should just be able to tap on) to be a safety issue.